Electro-hydraulic relay



Nov. 26, 1957 W, G, HOLZBOCK A 2,84,183

ELECTRO-'HYDRAULIC RELAY Filed May 25. 1956 2 Sheets-Sheet 1 /A/vEn/rak Nov. 26, 1957 w. G. HoLzBocK ELECTR0HYDRAULIC RELAY 2 Sheets-Sheei 2 Filed May 25. 1956 A /M/f/Wa WernerI G. Holzback United States liatent ELECTRO-HYDRAULIC RELAY Werner` G. Holzbock, Evanston, lll., assigner to Askania Regulator Company, Chicago, Ill., a corporation of Illinois Appiication May 25, 1956, Serial No. 587,316

Claims. (Cl. 60-52) The present invention relates to a hydraulic relay regulator assembly wherein the regulator itself comprises the well known hydraulic jet pipe. Such a regulator comprises a pivoted jet pipe provided with an axial discharge oriiice that continuously delivers a jet of pressurized fluid toward a pair of narrowly spaced receiver ports in a distributor structure. The jet pipe is pivoted for swinging in the directions of spacing of the ports. The relative degrees of registration of the discharge orifice with the different ports determines magnitudes of pressures developed in them by kinetic energy of the owing uid impinging therein, and so regulates balance, or sense and magnitude of differential between pressures developed within the two ports, and in turn the relative magnitudes of pressures of the diierent iluid inputs to a reversible hydraulic power unit which inputs respectively are connected to those ports. Further, the invention relates to such an assembly wherein the signal means comprises an electrical coil, or plural coils, mechanically connected to the jet pipe and movable in a magnetic field of constant intensity. Thereby the intensity of magnetic eld developed by the coil, and the magnitude and senses of the interacting permanent magnet and coil ields, are determined by the magnitude and polarity of a signal current or relative magnitudes and polarities of signal currents, energizing the coil or coils. The characteristics of a spring return or centering system that opposes deflection of the jet pipe by the electromagnetic system determines the position of the jet pipe, and consequently the relationship of the port pressures.

The general combination of a moving signal currentcarrying coil, and a jet pipe positionable thereby, is disclosed in United States patents to Guido Wunsch 2,038,- 465 and 2,062,922 and to Wunsch et al. 2,052,375. Apparently there has been little commercial exploitation or practical development of such regulators, possibly due to deciencies in permanent magnets. Recently, the highly developed and perfected alloy magnets developed for loudspeaker service have rendered such relay regulator systems completely practical. Primarily the object of the present invention is directed to provision of an assembly, arranged in novel fashion to obtain high eiliciency, dependability, repeatability and generally satisfactory performance from a system of the'kind in question. Another object is arrangement of such an assembly as a preassembled unit adapted to convenient manufacture, installation and adjustment. A further object is the provision in such an assembly of novel arrangements of centering springs and operation-proportioning mechanism.

In the accompanying drawings:

Fig. l is a vertical median section of an assembly embodying the invention.

Fig. 2 is a top plan thereof.

lFig. 3 is a partially broken elevation from the left side of the assembly as seen in Fig. 1.

Fig. 4 is a fragmentary elevation of the opposite side ofthe assembly.

Tice

Fig. 5 is a schematic vertical sectional view of a complete relay assembly embodying the invention.

Describing the drawings in detail, the assembly comprises a main body structure 7, such as a casting, which contains a -cylinder 8 wherein is movable a piston 9, and the ends of which are closed in conventional fashion by heads 10. Advantageously and as shown, and for reasons to be described, cylinder 8 is arranged for vertical disposition when the assembly is installed. At one side of cylinder 8 and alongside its bottom portion, body structure 7 is provided with a projection 11 that serves as the distributor for the hydraulic jet, and the upper surface of which is provided with a pair of receiver ports 12, 13, shown as being in an insert plate 14. Ports 12, 13 respectively communicate with the different cylinder ends by passages 15, 16, as indicated in Fig. 5, and partially in Figs. l and 3, and which are provided in body structure 7. Advantageously spacing of ports 12, 13 is along a radius of cylinder 8.

Spaced above projection 11 is a pair of projecting ears 17, which may be bolted on attachments, and between which is mounted for rotative movement the spindle support 18 of jet pipe 19, the arrangement being such that the path of the discharge orice in the tip 20 of the jet pipe, during swing of the jet pipe, is along the radius in which ports 12, 13 are centered. To this end the pivot axis of jet pipe swinging is disposed tangent to an arc centered on the cylinder axis. As best shown in Fig. 3, one half of spindle 18 is provided with a supply passage 21 that communicates with jet pipe delivery passage 22, and the end of this spindle half is supported by a fluid conducting bearing 23 to which` iiuid is supplied through a bore 24 in the corresponding supporting ear 17.

A frame 26 is supported by and above ears 17 and mounts the permanent magnet 27. Magnet 27 is of annular arrangement, with pole pieces 28, 29 defining an annular gap 30. The axis of gap 30, in correspondence to orientation of the jet pipe pivot axis, is arranged on a radius of cylinder 8 that is perpendicular to the plane of the jet pipe pivot axis. Attached to the jet pipe assembly 18, 19, is an operating arm 31 that carries the signal coil system 32, the angular position of arm 31 being so related to that of jet pipe 19, and the location of the coil system 32 being so positioned that the latter is movable axially in gap 30 as arm 31 and jet pipe 19 swing in response to variations in current or currents energizing the coil system 32.

A spring return or centering system includes a rst spring 35 connected between the free end of arm 31, which is extended to above frame 26, and a tension adjusting screw 36 mounted in a part 37 xed to the magnet assembly. The remainder of the return or centering system is included in a system for proportioning distance of movement of piston 9, to the degree of that deection of jet pipe 19 from a neutral position wherein its discharge orifice is in equal degrees of registration with ports 12, 13. The latter constitutes a mechanical restoring system that returns the jet pipe to its neutral position when piston movement through a distance corresponding to the degree of such jet pipe deflection has been completed.

This operation proportioning, jet pipe restoring system y comprises a piston rod 39v that slidably penetrates the upper cylinder head 10 and that moves a bell crank 40 that is pivotally mounted on a cross shaft 41 extended between a pair of supports 42 that project from frame 26 and ears'17. Bell crank 4i) has a first arm 43 that extends across and above the top of the part of structure 7 enclosing cylinder 8, and alongside piston rod 39, and a second arm 44 that is coupled to operating arm 31 through a transmission element, shown as a spring 4.5.

Adjustment of the tension of spring 45 is provided by a,`

screw 46. Arms 43, 44 are connected by a bearing element 47 that rotatively surrounds cross shaft 41. Piston rod 39 positions bell crank arm 43 as the piston moves, correspondingly altering tension of spring 45, and, with ports 12, 13 connected to the different cylinder ends .in correct senses, tending to move jet pipe 19 toward its neutral position as a consequence of drive of piston 9 1n response to deflection of the jet pipe from that position.

ln order to provide the very desirable feature of adjustment for selection of a particularproportional relation between distance of piston response and degree of jet pipe deflection, the assembly is arranged to permit selection of the effective length of lever arm provided by first bell crank arm 43, through which movement of piston 9 is transmitted to second crank arm 44 and spring 45. To this end a transverse member, conveniently a laterally open channel 49, is mounted on piston rod 39, and is provided wtih a track slot 50 along which a carriage 51 is movable, the carriage being provided with a holding arrangement settable by a screw 52. A roller 53 contacts the underside of bell crank arm 43. Adjustment of carriage 51 and transmission roller 53 along member 49 and crank arm 43 serves to adjust the distance of the piston movement necessary to counterbalance a given variation in magnitude of current energizing coil system 32.`

A spring 55 coupled between crank arm 43 and a fixed part of the assembly constitute a third element of the jet pipe return spring system, and additionally exerts force to maintain arm 43 in contact with roller 53, to insure that the bell crank follows inward movement of piston rod 39.

Operation of the assembly is readily understandable. Assuming that jet pipe 19 is in its neutral position, and that piston 9 consequently is motionless, a change in magnitude of current energization coil system 32 will move the coil system and arm 31, and deflect jet pipe 19. Consequently, pressures across piston 9 will become unbalanced and the piston will move in a direction corresponding to sense of that unbalance and direction in which the jet pipe has been deflected. Such movement will swing bell crank 40 and change the force exerted on arm 31 by spring 45 in opposition to the change in force that resulted from the current change. This results in restoring jet pipe 19 to its neutral position and terminating piston movement when the distance traveled by the latter has reached the preselected proportional relation, set by the position of carriage 51, to the degree of jet pipe deilection and the magnitude of current change that caused it. Upon arrival of the jet pipe at its neutral position piston movement ceases due to rebalance of pressures in the opposite cylinder ends. v

A second piston rod 55 extended through the lower cylinder head serves as the output member of the assembly, and either it or some positionable element connected to it may constitute the member which is to be positioned in correspondence to magnitude of some condition represented by the magnitude of current energizing coil system 32. Obviously the latter may be arranged in various ways, for energization by one or more currents each of which represents a factor to be included in control of the position of rod 55, and fed to seystem 32 in suitable bucking or aiding polarities.

Fig. shows a unit type of installation to which the assembly described above is particularly suited. The entire assembly is enclosed in a tank 57 wherein is contained a body 58 of hydraulic operating fluid, as oil, of a depth to Submerge at least the jet pipe top and distributor. Such submergence is desirable since it tends to eliminate entrainment of air and its injection into the receiver ports and transmission lines, 15, 16, and also tends to eliminate interference with regular and uniform jet delivery by surging and turbulence. A pump 59 is supported in tank 57 and driven by a motorM mounted on the tank top, for delivery o'f fluid to jet pipe 19. Signal current is fed to coil'system 32 Yby leadwires 60 that/enter the tank through suitable seals in the wall. Piston rod 55 is extended through an opening 61 in the tank bottom, for connection to a positionable member disposed below tank 57.

From the foregoing the structure, arrangement and general type of assemblies embodying the invention and making use of its features and advantages will be apparent, and it is to be understood that the limits and bounds of patent protection are defined by and to be ascertained from the lappended claims rather than by the foregoing detailed and wholly exemplary disclosure.

I claim:

1. An electrohydraulic relay assembly comprising structure enclosing a cylinder, a piston movable in said cylinder and at least one transmission member operatively connected to said piston and movably extended thro-ugh a portion of said structure to its exterior, a jet pipe having an axial passage and its free end provided with a discharge orifice, and pivotally supported by said structure for swinging about a fixed pivot axis from which said jet pipe projects in substantially radial disposition, an operating arm attached to said jet pipe and projecting in fixed angular positional relation thereto, an electrical coilv mounted on said arm with its axis disposed substantially perpendicular to a plane wherein said jet pipe pivot axis lies, a permanent magnet supported by said structure and having an annular gap positioned for movement of said coil therein, conduit means for delivering fluid under pressure to said jet pipe passage for discharge through said orifice', distributor means supported` by said structure and provided with a pair of receiver ports facing the path of movement of said jet pipe orifice, said ports being narrowly spaced in the directions of movement of said orifice as the jet pipe is swung, and the different said ports respectively being connected with different ends of said cylinder by passages in said structure, and proportional piston movement control means comprising transmission linkage connected between said transmission member and said operating arm for restoring the latter to a position from which it has been deflected upon completion of movement of said piston through a distance having a preselected proportional relation to the degree of that deflection.

2. An electrohydraulic relay assembly comprising structure enclosing a cylinder, a piston movable in said cylinder and at least one piston rod secured to said piston and slidably extended through an end wall thereof, a jet pipe pivotally supported by said structure for swinging about a fixed axis disposed in substantially tangential relation to an arc centered upon the axis of said cylinder and having an internal passage and a discharge orifice in its free end, an operating arm extended from said jet pipe in an angular position for movement in directions extended substantially transverse to directions of movement of said piston rod and toward and away from it, an electrical coil' supported by said arm with its axis disposed substantia'lly in radial relation to said cylinder axis, a permanent magnet having pole pieces forming an annular gap andy supported by said structure with said gap disposed for movement of said coil therein, a bell crank pivotally supported by said structure for swinging about a fixed axis disposed in spaced relation to said piston rod and substantially tangential relation to an arc centered on said cylinder axis and lying in a plane substantially .perpendicular to said coil axis, said crank having one arm pivotally coupled to said rod for swinging by the latter as it moves, transmission means extended substantially in the directions of said coil axis and connected to said operating arm and the second arm of said bell crank, conduit means 'for supplying fluid under pressure to said jet pipe passage, and distributor means supported by said structure and having a pair of receiver ports facing saidl orifice, said ports being narrowly spaced in the directions of movement of said jet pipe orifice as the jet pipe swings, and the different said ports respectively being connected with diierent ends of said cylinder by passages in said structure and in senses to produce movement of said piston, rod, bell crank and operating arm in directions to restore the latter and jet pipe to a neutral position wherein its orifice is in equal registration with said ports following its deflection from that position and by development of pressure diierential in the different cylinder ends as a consequence of unequal registration of said oriice with the different said ports.

3. An electrohydraulic relay assembly according to claim 2, wherein said transmission means comprises a spring arranged to translate movement of said piston rod and bell crank in response to a deflection of said operating arm and jet pipe, into a force change exerted on said operating arm in opposition to .a change in force exerted thereon by said coil and that has resulted in that deflection.

4. An electrohydraulic relay according to claim 2, including first and second centering springs each having a first end connected to said structure, one having its second end connected to said operating arm and the other having its second end connected to said bell crank, said springs being tensed to position said operating arm and jet pipe with the latter in its said neutral position while said coil is unenergized.

5. An electrohydraulic relay assembly according to claim 2, wherein said transmission member comprises a spring arranged to translate movement of said piston rod and bell crank in response to a deflection of said operating arm and jet pipe, into a force change exerted on said operating arm in opposition to a force change thereon exerted by said coil and that has resulted in that deliection, said assembly including rst and second centering springs each having a first end -connected to said structure, one having its second end connected to said operating arm, the other having its second end connected to said iirst bell crank arm, and said transmission and centering springs being tensed to position said operating arm and jet pipe with the latter in its said neutral position while said coil is unenergized.

6. A hydraulic relay assembly according to claim 2, including a member carried by said piston rod and having a surface extended substantially transverse to the directions of movement thereof and alongside and spaced from a surface of said first bell crank arm, that extends toward and away from the axis of bell crank swinging, and a traveller member movable along said surfaces for changing the lever arm length of said lirst bell crank arm through which motion of said piston rod and transverse member is transmitted to said transmission member.

7. A hydraulic relay assembly according to claim 2, wherein said jet pipe is disposed with its axis substantially parallel to ythe axis of said cylinder.

8. A hydraulic relay assembly according to claim 2, wherein said jet pipe and receiver ports are so disposed that the axis of the former is substantially parallel to the axis of said cylinder while its oriec is in equal registration With the two said ports, said fixed axis of pivoted jet pipe mounting is radially spaced from said cylinder axis and disposed in a plane substantially perpendicular 6 thereto, said bell crank pivot axis is substantially parallel to said jet pipe pivot axis, and said coil axis is disposed substantially radial to said cylinder axis.

9. A hydraulic relay assembly according to claim 2, wherein said cylinder is disposed with its axis substantially vertical, said jet pipe pivot axis is radially spaced from said cylinder axis and is tangent to an arc centered on the latter, said receiver ports are so disposed that said jet pipe is substantially vertical while its orifice is in equal registration with both said ports, said bell crank pivot axis is spaced above said jet pipe axis, is parallel thereto, and located between it and the axis of said cylinder, and said coil axis is disposed substantially radial to said cylinder axis.

10. A hydraulic relay assembly for positioning a controlled member in correspondence to magnitude of an electrical signal current, comprising a tank, structure secured to the bottom of said tank and enclosing a cylinder disposed with its axis substantially vertical, a piston movable in said cylinder and piston rods respectively extended from said piston slidably through the different end walls of said cylinder and the lower one thereof projecting below said tank bottom through an opening therein and constituting said controlled member, a jet pipe pivotally supported within said tank for swinging about a substantially horizontal axis located outside said cylinder, and from which said jet pipe extends radially, said jet pipe having an internal .axial passage and an axial orice in its free end for discharge of a liquid jet, a distributor structure having a pair of receiver ports spaced narrowly in the directions of movement of said orifice as said jet pipe swings, means providing passageways connecting the diierent said ports respectively with opposite ends of said cylinder, an operating arm secured to said jet pipe and extended in a preselected angular relation to said jet pipe, an electrical coil secured to said arm with its axis disposed substantially perpendicular to a plane wherein said jet pipe pivot axis lies, a permanent magnet having pole pieces forming an annular gap disposed for movement of said coil therein; spring means biasing said arm and jet pipe to positions wherein said jet pipe orifice is in equal registration with said receiver ports, a system for proportioning motion of said piston to the magnitude of current energizing said coil comprising -transmission linkage coupled between the upper said piston rod and said operating arm and arranged to restore said pipe to a position wherein its orice is in equal registration with said ports, from which a change in magnitude of current energizing said coil has deliected it, upon completion of movement of said piston through a distance having a preselected proportional relation to the magnitude of that current change, a body of oil in said tank of a depth submerging said jet pipe oriiice and distributor structure, and oil supply means comprising a pump and piping arranged in said tank for continuously supplying oil from said body and under pressure to said jet pipe passage.

Ray Apr. 30, 1946 Ziebolz Jan. l1, 1955A 

